Sublime

Plath's description of the blackberries and of the sea evokes a simultaneous sense of awe and reverence best characterized in the idea of the "sublime." The idea of the sublime was hotly debated in the eighteenth century and later appeared in the work of romantic poets such as William Wordsworth, whose writing is marked by speakers aware of their own smallness in relation to the grandeur and might of nature. The final image of "Blackberrying" adds terror to the sense of awe, as the speaker describes

a great space
Of white and pewter lights, and a din like silversmiths
Beating and beating at an intractable metal.

Consciousness

In packing her poem with images of life's abundance and death's inevitability, Plath points to the uniqueness and the "problem" of human existence: human beings are aware that they will die and there is nothing they can do to change that...